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arXiv · 1101.0193

Antiferromagnetic long range order in the uniform resonating valence bond state on square lattice

Tao Li
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Abstract

With extensive variational Monte Carlo simulation, we show that the uniform resonating valence bond state(U-RVB) on square lattice is actually antiferromagnetic long range ordered. The ordered moment is estimated to be $m\approx 0.17$. Finite size scaling analysis on lattice up to lattice size of $50\times 50$ shows that the spin structure factor at the antiferromagnetic ordering wave vector follows perfectly the $\mathrm{S}_{\mathrm{q}=(π,π)} \simeq S_{0}+α(1/L)^{5/4}$ behavior, where $L$ is linear scale of the lattice. Such a behavior is quite unexpected from the slave Boson mean field treatment or the Gutzwiller approximation of the uniform RVB state.

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Tao Li. 2011-08-02. Antiferromagnetic long range order in the uniform resonating valence bond state on square lattice. https://doi.org/10.1209/0295-5075%2F103%2F57002

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